NASCAR and the participating manufacturers have cool-looking cars for the coming season, and they spent last week showing off their 2013 racers during the annual media tour in North Carolina.

The sport created incredible enthusiasm for the cars with an intense marketing campaign — NASCAR even labeled these cars its "Gen-6" although it never so labeled the first five generations of Sprint Cup cars.

The previous car — typically called the "car of tomorrow" — didn't enjoy much positive press in its debut. Kyle Busch won the first COT race in 2007 and promptly criticized the car template and the way it drove. That only added to the negative vibe about what many considered a car that had improved safety features but an unappealing look.

To avoid a repeat of that marketing disaster, NASCAR spent the 2012-13 offseason trying to pump up its new cars, whose body features correlate much better with the manufacturers' passenger vehicles.

The cars have a sleeker appearance with a smaller greenhouse and curved noses along with rear bumpers that are much less square than in the past. They resemble the three manufacturers' showroom models — Ford Fusion, Toyota Camry and Chevrolet SS, a new production car to be introduced at Daytona in February and available in August.

"We just had this blocky-looking car," four-time Cup champion Jeff Gordon said. "It wasn't a sexy-looking car. We made that car a really good racecar. It took awhile and we did."

The key for NASCAR is how long will it take for teams to make their 2013 Cup car, as Gordon puts it, "a really good racecar."

NASCAR teams and officials spent last year testing, teeter-tottering in enthusiasm as they went from optimistic about the cars' potential and discouraged when a test didn't go as planned to renewed optimism as tests in late 2012 showed progress.

They believe they found a good starting point for 2013. The cars are 160 pounds lighter (100 pounds on the right, 60 pounds on the left), which should reduce stress on right-side tires. A bigger spoiler and the use of carbon fiber hoods and deck lids will help with rear downforce on non-restrictor-plate tracks as teams can better adjust weight. The cars will steer differently because they do not have rear sway bars and tire camber is nearly twice (from 1.8 degrees to 3.5 degrees) what it was last year.

"Everything is designed to have closer competition. … What are the things we can do with almost a clean sheet design to tighten up and close the racing up even tighter than it already is," NASCAR chairman Brian France said. "And we're learning some things (through testing).

"We're using a lot more engineering, a lot more third-party expertise to accomplish that, and I'm quite satisfied that we're going to be on (track and) it will be a continual thing for us to get right."

France said he will measure the new cars' success by lead changes and closeness of competition.

"The odds are the on-track passing and things of that nature is not going to change right away," defending Cup champion Brad Keselowski said. "But the potential is there.

"The car looks a lot better. It's a major improvement and a showing to me of the commitment to the sport of getting it."

Much of the cars' success will depend on tires Goodyear selects for the various tracks, Keselowski said.

Until teams know which tires they will use on at which tracks, they won't know where to test. Although each organization gets four tests at tracks on the circuit, it cannot use a tire until compounds have been raced. So if Goodyear decides on a new compound to use for intermediate tracks (1.5-mile and 2-mile downforce-dependent tracks), teams likely will wait until after the first race to do extensive testing so they can use the exact type of tire they'll have on race day.

"It's NASCAR's intent to give us a car more stable aerodynamically to create more side-by-side racing to give us an opportunity to be more aggressive on restarts," five-time Cup champion Jimmie Johnson said. "If you have more downforce, you might be more willing to force your way into a situation side by side with someone.

"The car is very comfortable with all the downforce. Speeds are up."

Johnson and other drivers said the cars steer much differently with changes in the rear suspension rules. NASCAR changed ductwork and enabled teams to have more options in weight distribution.

"It's going to take some time to really understand the new car and where it sort of is and where it fits me," Dale Earnhardt Jr. said. "I didn't think the COT was a very good fit for me. I struggled with the car.

"You couldn't overdrive the car at all, even a half a car length into the corner and the car would get pissed off at you and it was such an annoying thing to deal with every lap trying to get hat car to go around the corner, having to drive in this little window of grip was really difficult."

Earnhardt said while Gen-6 cars were incredibly fast and had great grip at Charlotte tests, temperatures were cooler than they will be on race days and the track had more grip than most.

"NASCAR made a lot of aerodynamic changes to help the second car be able to pass the first car," Joe Gibbs Racing driver Denny Hamlin said. "The only challenge we're going to have is that they're running so fast.

"It's going to be hard to see a variance of speed from one car to the next."

Veteran Mark Martin likes his new car but worries the tolerances are so tight a team might slightly tune its car's ride height during a race and make it illegal by postrace inspection.

Other than that, Martin doesn't see a big difference from a technical aspect.

"They did some things to take some skew — to keep the cars from running as crooked — and they gave us something else to compensate for that, so at the end of the day it was not going to be dramatically different," Martin said. "It's not reinventing the wheel. It's not like going from the '79 big cars down to the (smaller) cars, that was dramatic, and going from the car to the COT, that was a dramatic change.

"This was a subtle improvement in everything except the aesthetics."

NASCAR hopes for more than just subtle improvement — and more importantly, immediate improvement.

Keselowski is among drivers switching makes after Dodge's withdrawal from NASCAR. He preached patience, saying he would believe in Gen-6 car potential for at least 18 months to work through the kinks. He knows fans won't give NASCAR that long.

"It's naive to think that it would be the end-all, be-all, cure-all of all that ails American motorsports," Keselowski said. "It's a step in the right direction and it's a big step. That's what it is.

"It's a great car. It's beautiful. But right now it's a beautiful car and that's it. Until it gets on the track and shows a result that our fans can connect to as far as the level of competition, it's just a beautiful car."